The overall aim of the proposed research is to find possible causal relationship between the methylation of nuclear proteins and growth of tissues, with the following objectives: (1) To investigate the possible relationship between the extent of methylation of nuclear proteins (histones and non-histone chromosomal proteins) and the degree of differentiation and rate of growth of neoplastic tissues and (2) To study the levels of various methylating and demethylating enzymes during liver regeneration and growth of neoplasms. BIBLIOGRAPHIC REFERENCES: Labile protein-methyl ester: Comparison between chemically and enzymatically synthesized. Kim, S. and Paik, W. K., Experientia, 32, 982 (1976). S-Adenosylmethionine:protein-arginine methyltransferase. Purification and mechanism of the enzyme. Lee, H. W., Kim, S. and Paik, W. K., Biochemistry, 16, 78 (1977).